预先冷变形及快速加热复合处理对65Mn钢的组织与性能的影响

Effect of Pre-Cold Working and Rapid Heating Compound Treatment on the Microstructure and Property of 65Mn Steel

本文介绍了65Mn钢经预冷变形后快速加热淬火复合处理对材料的强塑性的影响.试验结果表明,经复合处理的65Mn钢丝可达到σ(?)=1900～2000MPa,φ=(45～50)%的水平,与普通工艺处理相比其抗拉强度增值100～150MPa,断面收缩率增值5～10%。最佳工艺为:预冷变形50～80%。50℃/(?),800～820℃加热淬火,350℃回火.经此工艺处理后的晶粒度达到12～13级。文中还论述了组织与强化机理,指出冷变形时形成的位错在快速加热淬火下经α→γ→α′相变遗传给α′是钢获得高强韧化效果的原因.

This paper reports the combination effects of pre-cold working and rapid heating and quenching on the mechanical property of 65Mn steeL The test results showed that(1) 65Mn steel wire treated by this compound treatment possess the level of σ. 1900～2000 MPa and Ψ 45～50%. In comparison with the conventional treatment without pre-cold working, the net increasement of σ_b and Ψ are 100～150 MPa and 5 ～10% respectively. (2)The optimum process parameters are as follows: pre-cold working 50～80%, heating rate 50°C/s, quenching at 800～820°C, tempering at 350°C. After treated with these parameters the grain size of the steel could be reached to 12～13ASTM. (3)The microstructure and strengthening mechanism are also discussed. It is pointed out that the dislocations forme din the pre-cold working under rapid heating and quenching will be inherited to α'during α→γ→α' transformation are the main reason which strength and toughness of the steel could be raised.